I saw all the stuff about tuning 12 strings and the use of capos. I've ben playing 12-string about 25 years now - my guitar is an Epiphone Nova 245. It works at concert pitch with light gauge strings and also when detuned a tone with slightly heavier 5th and 6ths. I sing and also accompany a lot of singers and the capo is essential - someone will always want it 'up a bit' at the last minute. With the thicker strings I use 2 (!) Shubb capos to hold the strings down firmly and get a clear tone.
Important: a capo will almost always put the octave (thinner) strings on the 4th 5th and 6th strings out of tune slightly - its stretching them a fraction more than the thicker bass strings. Its probably just a quarter turn on the machinehead but it needs doing! The thicker the strings and the higher the action of the guitar the more you need to do it. Cheap or badly set up guitars also go 'out of tune' as you go higher up the neck because of the extra tension to hold the string down. If you're checking out a guitar in a shop, try playing the e minor chord using the 5th string at the 7th fret and the 4th string at the 9th fret with all the other strings open and see if all sounds in tune!
Hope this is all helpful - Happy Playing